In electronics a NOT gate is more commonly called an inverter. The circle on the symbol is called a bubble, and is used in logic diagrams to indicate a logic negation between the external logic state and the internal logic state (1 to 0 or vice versa).
A weather watch, on the other hand, typically refers to an alert issued to indicate that conditions are favorable for the development of dangerous weather patterns, although the dangerous weather conditions themselves are not currently present.
Severe Weather Awareness: Difference Between a Watch & Warning â The National Weather Service is the official issuer of a watch or a warning, based on expected weather conditions. Stormcenter7 Meteorologist Brett Collar explains the difference. In severe weather season, knowing the difference between a watch and a warning can be life-saving.